And since Ubuntu Wily ships 2.3, I presume this is also fixed in Ubuntu in Wily. I'll mark that Fix Released too, and add a task for Trusty.
** Changed in: qemu (Ubuntu) Status: New => Fix Released ** Also affects: qemu (Ubuntu Trusty) Importance: Undecided Status: New ** Changed in: qemu (Ubuntu Trusty) Status: New => Triaged ** Changed in: qemu (Ubuntu Trusty) Importance: Undecided => Medium -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1422307 Title: qemu-nbd corrupts files Status in QEMU: Fix Released Status in qemu package in Ubuntu: Fix Released Status in qemu source package in Trusty: Triaged Bug description: Dear all, On Trusty, in certain situations, try to copy files over a qemu-nbd mounted file system leads to write errors (and thus, file corruption). Here is the last example I tried: -> virtual disk is a VDI disk -> It has only one partition, in FAT Here is my mount process: # modprobe nbd max_part=63 # qemu-nbd -c /dev/nbd0 "virtual_disk.vdi" # partprobe /dev/nbd0 # mount /dev/nbd0p1 /tmp/mnt/ Partition is properly mounted at that point: /dev/nbd0p1 on /tmp/mnt type vfat (rw) Now, when I copy a file (rather big, ~28MB): # cp file_to_copy /tmp/mnt/ ; sync # md5sum /tmp/mnt/file_to_copy 2efc9f32e4267782b11d63d2f128a363 /tmp/mnt/file_to_copy # umount /tmp/mnt # mount /dev/nbd0p1 /tmp/mnt/ # md5sum /tmp/mnt/file_to_copy 42b0a3bf73f704d03ce301716d7654de /tmp/mnt/file_to_copy The first hash was obviously the right one. On a previous attempt I did, I spotted thanks to vbindiff that parts of the file were just filed with 0s instead of actual data. It will randomly work after several attempts to write. Version information: # qemu-nbd --version qemu-nbd version 0.0.1 Written by Anthony Liguori. Cheers, To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1422307/+subscriptions